The games we play in zapsmall might apply to your current question. zapsmall rounds to a specified number of digits. The initial intent of zapsmall was to display 10^(-16) as 0. Rich
> tmp <- c(1, 1 + c(-1,1)*10^(-14)) > tmp [1] 1 1 1 > unique(tmp) [1] 1 1 1 > unique(zapsmall(tmp)) [1] 1 > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.